No matter how many years of experience you have had towing a trailer down the road, any driver can experience loss of control over their trailer without warning. And if you have ever experienced that scary moment when trailer sway begins, you know it’s important to react appropriately. Trailer sway is a common cause of accidents involving trailers. Here are the steps you can take to decrease the amount of trailer sway and avoid causing an accident.
- Avoid stepping on the brake pedal! This will likely be against your natural instinct, but braking suddenly can make the sway worse and cause you to lose control. You should remove your foot from the accelerator, so your speed reduces gradually.
- Keep the steering wheel straight. Attempting to fight the sway by turning the wheel will only make it worse and accentuate the problem.
- Let your vehicle slow down on its own.
- If you have trailer brakes, you can manually apply them very gently.
- In some cases, a slight increase in speed can put forward pressure on the trailer tongue and straighten it a bit. Do NOT increase your speed if you are going downhill.
- Once you have regained control, pull over to a safe area and check your cargo to see if it shifted or needs to be moved around, so more weight is at the front of the trailer.
- Get your hitch inspected to ensure it is not defective. Replace it if necessary.
- Consider upgrading your brake control system and adding a weight distribution hitch.
What Causes Trailer Sway?
Wind Gusts: Wind is the most common cause of trailer sway. When there is a strong force pushing your trailer from one side or the other, it can cause it to sway from side to side. This is usually the result of strong gusts of wind or passing a high-profile vehicle such as an 18 wheeler who is traveling at high speeds.
Excessive Speed: Many of the tires that come on a trailer are only rated for speeds up to 65mph, but many highway speeds allow you to go 70-75mph. While its tempting to speed up to get where you’re going quicker, it could be the difference between arriving safely or experiencing trailer sway.
Excessive weight or improper weight distribution: Excessive weight could be in the tongue weight or the weight of your trailer load. If the trailer is too heavy, it can cause the tow vehicle to squat and make the rear “squirm,” which then creates sway in the trailer. If too much of the heavy weight is at the back of the trailer, this can also be a problem. The tongue weight should be around 15% of the total weight of the trailer to avoid squat as well.
Low Tire Pressure: Without enough tire pressure on either the trailer or tow vehicle tires, the sidewalls can start to bow and compress. Inflating the rear tires of the vehicle to the maximum recommended pressure should keep them from becoming too compressed. Check the tire pressure at stops along your trip and add air when needed.
How To Prevent Trailer Sway
SwayPro: The safest and most effective way to prevent trailer sway is through use of the Blue Ox SwayPro. This weight distribution hitch stops trailer sway before it starts by using tension to keep its spring bars taut, and the attached brackets ensure those spring bars keep the trailer in line with the towing vehicle. It is very user-friendly and allows you to back up without needing to disconnect. The SwayPro can help prevent sway caused by any of the reasons mentioned above.
Stiff Tires: If you are towing with an SUV or a passenger vehicle, it likely came with Passenger tires designed to give you a smooth ride. Switching to Light Truck tires that are stiffer and designed for heavy loads can reduce the rear end “squirm” and reduce the chances of sway.
Tongue Weight Scale: Having a tongue weight that is too high or too low can increase the likelihood of trailer sway. A tongue weight scale is easy to use and may be worth the investment if you often tow or have multiple trailers in use.